Wearable chemical dispenser

ABSTRACT

Disclosed herein are wearable devices for dispensing insect repellents, fragrances, and/or other chemicals along the outside of the clothing of a human, to avoid the need to apply such chemicals directly to clothing or to human&#39;s skin. The devices have an on/off switch that automatically controls a shutter which enables and restricts air flow, while also controlling fan operation and covering of a use-up cue. The device also is designed to prevent fan operation when an impregnated slab is not present. Also disclosed are preferred refills for use with such devices.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH/DEVELOPMENT

Not applicable

BACKGROUND OF THE INVENTION

The present invention relates to wearable devices that dispensechemicals such as insect repellents and/or fragrances.

Various techniques have been developed to provide humans with protectionfrom insect bites. For insect control inside buildings a primaryemphasis is placed on trying to keep insects from entering the buildingat all (e.g. placing screens over windows). This sometimes issupplemented with chemical treatment of room air and/or the use oftraps. See e.g. U.S. Pat. Nos. 6,582,714 and 7,175,815, and also U.S.patent application publications 2005/0079113, 2006/0039835, 2006/0137241and 2007/0036688.

When the individual is outdoors where the area can't be effectivelyscreened, and the individual is mostly staying in a particular area(e.g. at a picnic, or on a patio near a building), traps and repellentsare the primary focus. For example, a common approach is to use candles(e.g. citronella candles) or other dispensing devices which disperserepellents such as citronella into the air.

Alternatively, and in any event when the individual is moving away froma single area that they control, individuals often apply an insectrepellent to clothing or directly to their skin. The source of repellentprotection thus moves with the individual.

However, if a consumer does not read the label or other instructionsassociated therewith they may not understand how long a particularapplication of the chemical is likely to remain most effective. This maylead the consumer to prematurely apply additional product before it isnecessary to do so, thereby increasing the overall cost of protection.Alternatively, they may not make a repeat application of product soonenough, until after the effectiveness of the product has decreaseddramatically. This may lead to consumer dissatisfaction.

In any event, some conventional insect repellent sprays/lotionssometimes raise concerns deriving from the location where the chemicalis to be applied. For example, where the product is intended to besprayed on clothing, this will limit how the spray is formulated (e.g.to avoid using certain otherwise preferred solvents or actives that canstain certain fabrics). This can increase costs, or require somecompromises with respect to other desired attributes (e.g. perceivedfeel). Moreover, even where the formulations are designed to be sprayeddirectly on even very delicate clothing, consumers may be unwilling totest that out, and thus avoid the product regardless of its suitability.

Similarly, notwithstanding suitability, some consumers have expressed areluctance to apply insect repellents directly to their skin. Again,this can lead to consumers avoiding products which direct that type ofapplication.

As a result, the art has attempted to develop compact, portableelectrical devices having a fan and an insecticide source therein. Thesedevices may have a clip so that they can easily be mounted on a belt, apurse, or even a pocket, and thus be “worn” by the consumer as they moveoutside. The device may draw air through, or blow air past, a substrateimpregnated with an insect repellent or other air treatment chemical,thereby dispensing the active into the air, preferably (in the case of arepellent) downward along the outside of a human's clothing. See e.g.U.S. Pat. Nos. 6,296,902, 7,007,861, 7,152,809, and 7,168,630, and U.S.patent application publication 2003/0175171.

There have even been a variety of attempts to develop use indicatorsassociated with air treatment devices, so that consumers can tell whenthe device needs servicing/refilling. See e.g. U.S. Pat. Nos. 4,062,649,4,293,095, 4,824,827, 5,293,648. See also U.S. Ser. No. 11/609,923,filed Dec. 13, 2006.

However, some such devices blow the active too far out away from thehuman body, causing too little of the active to reach locations ofprimary concern (e.g. near ankles). Other such devices don't provide away of minimizing waste of the active, such as while blower operation issuspended between uses. Still other such devices are unduly costly, aretoo heavy, or have other deficiencies (such as not providing sufficientfeedback to the consumer when the device is otherwise operatingineffectively).

Hence, a need exists for improved devices for dispensing insect controlactives and other air treatment chemicals, particularly those that canoperate without applying chemicals directly to the skin or clothing.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a dispensing device for dispensing an airtreatment chemical. The device has a housing with an inlet and an outletand an electrically powered fan to pull air in through the inlet andexhaust the air through the outlet, creating an air stream through thehousing. There is also a switch for turning the fan on and off, and amovable shutter.

Particularly importantly the shutter blocks or at least restricts theair flow when in a first, closed position and allows the air to flowwhen in a second, open position. It also has a projection thereon thatinteracts with the switch so that moving the shutter to the second, openposition activates the switch to turn on the fan.

In preferred forms there is also a rotatable finger that must be rotatedby interaction with the projection of the shutter before the switch canbe activated. There is a table to receive and hold a substrate exposedto the air stream, where the substrate bears an air treatment chemicalto be dispensed. The substrate is held in interactive relation with thefinger so (as it is being installed) to partially rotate the finger froma designated position when no substrate is held by the table, to aselected position when a substrate is held by the table. When the fingeris in the selected position it can be further rotated there from bymovement of the projection as the shutter is moved to activate the fan.

In other preferred forms the substrate comprises a use-up cue thatchanges appearance by evaporation of a material in a direction towardthe table when the substrate is in place on the table, wherein thefinger has a side extension that, as the finger is rotated byinteraction with the projection of the shutter as the shutter is moved,moves from a position inhibiting the evaporation of material from theuse-up cue to a second position wherein evaporation of material from theuse-up cue is readily permitted. The shutter, when in its closedposition, can close both the inlet and outlet.

In another aspect the invention provides a refill substrate for use withsuch a device. For example, the substrate can have an air-permeablestructure containing the air treatment chemical to be dispensed, and asurface positioned to interact with the finger so as to rotate it to theselected position. It may also have a use-up cue such that, when thesubstrate is in place on the table of the dispensing device, the use-upcue changes appearance by evaporation of a material in a directiontoward the table and at a location such that a side extension of thefinger, when the shutter is in its closed position, blocks evaporationof material from the use-up cue.

In still another aspect of the invention there is provided a wearabledevice for dispensing an air treatment chemical. It has a housing havingan inlet for permitting air to enter into an internal cavity of thehousing and an outlet for permitting air mixed with air treatmentchemical to exit the cavity. There is also a power supply mounted to thehousing, a substrate positionable in the housing bearing an airtreatment chemical, a blower powered by the power supply and capable ofmoving air from the inlet adjacent the substrate so as to mix airtreatment chemical into the moving air, and then deliver a mix of airand air treatment chemical to outside of the housing, and a shutter thatcan control air flow through the device.

Preferably the shutter can restrict air flow through the inlet at a sametime the shutter restricts air flow through the outlet, when the blowerof the device is not operating. Further, the shutter can have linkedthereto a cam projection which, when the substrate is in the device andthe projection is moved to a selected position, can cause an activationof the blower. If the substrate is removed from the device movement ofthe cam projection to the selected position doesn't activate the blower.

Other preferred aspects include that the substrate has an air permeablesection bearing the air treatment chemical and a shell portioncontaining a volatile use-up cue chemical. There is a finger mounted forrotation on its own longitudinal axis. A portion of the finger canpermit diffusion of the use-up cue chemical from the shell when thefinger is in a first rotational position, and can restrict diffusion ofthe use-up cue chemical from the shell when in a second rotationalposition. Movement of a cam projection can drive the finger from thesecond rotational position to the first rotational position.

The finger preferably automatically moves to a third rotational positionwhen the substrate is not present, and when so positioned placing thesubstrate in the device can drive the finger to the second rotationalposition. When the finger is in the second rotational position a camprojection on the shutter can extend through a through slot on thesubstrate to drive the finger to the first rotational position, and whenthe finger thereby reaches the first rotational position the blower willbe activated.

In a further aspect the invention provides a refill substrate for usewith a wearable air treatment chemical dispenser. There is a slabstructure having opposed facing surfaces, a through hole extendingbetween the facing surfaces, an air permeable sheet extending across thethrough hole, the sheet bearing a volatile insect repellent, and asupport beam extending at least part way across the through hole tosupport the sheet.

In preferred forms the slab structure also has a shell cavity retaininga use-up cue chemical, the cavity having an essentially transparent wallalong one of the opposed facing surfaces, the shell cavity is covered bya peel-off cover along the other of the opposed facing surfaces, thereis a through slot positioned between the air permeable section and theshell, and there is an indentation along a peripheral portion of thesubstrate so as to help avoid insertion of the substrate in thedispenser in an inside out manner.

When the on/off switch is moved to the on position, the finger movesaway from covering an exit of the shell (permitting the use-up cuechemical to continue to diffuse). When operation of the device issuspended by movement of the on/off switch, the finger again covers theexit of the shell, preserving the use-up cue chemical when the fan isoff, and better coordinating the use-up cue life to that of theimpregnated substrate portion.

Biasing of the finger by a spring portion of the switch can cause thefinger to rest in a “third” rotational position when the substrate isnot present in the device. This position is preferably pointing morethan 45 degrees outward/upward. When the finger is so positioned a camedge of the cam projection can only move the finger rotationally awayfrom an operational position (e.g. clockwise). Thus, absent thesubstrate, the blower won't work even if a consumer tries to move theon/off switch towards an on position. This is a signal to the consumerthat they should first install the substrate before use of the blower.

When the substrate is positioned properly in the device, it willrotationally drive the edge of the finger downward to the second “ready”rotational position. This is a position from where the cam edge can thendrive the finger downward to an operational position. Hence, positioningthe substrate in the device enables, but does not by itself activate,blower operation.

When the finger is in the second rotational position the cam projectionon the shutter extends through a through slot on the substrate to beready to drive the finger to the first rotational position with afurther movement of the on/off tab. In this position enough return forceis placed on the spring switch so as to activate its internal connectionand enable blower operation.

The devices and refills of the present invention have a variety ofimportant advantages. A consumer merely needs to operate a single on/offswitch to control blower operation, shut off the entry and exit of airfrom the external environment between uses, and close off use-up cuechemical diffusion between uses. Structures associated therewith preventmotor operation when the impregnated refill has not yet been installed,and also prevent improper installation of the substrate.

These devices and refills are relatively inexpensive to produce, and aresuitable for consumers to understand and use without extensiveinstructions. Further, these devices can be made lightweight, and thuscan be worn hanging from a clothing item.

The foregoing and other advantages of the present invention will beapparent from the following description. In the description thatfollows, reference is made to the accompanying drawings which form apart thereof, and in which there is shown by way of illustration, andnot limitation, a preferred embodiment of the invention. As thisembodiment is merely illustrative, it is not intended to represent thefull scope of the invention. Thus, reference should therefore be made tothe claims herein for interpreting the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a left lower frontal perspective view of a preferreddispenser device of the present invention, in an “off” position;

FIG. 1B is a view similar to FIG. 1A, but with a shutter of thedispenser shown in the open position and the device on;

FIG. 2 is an exploded perspective view of the device of FIG. 1;

FIG. 3 is a view similar to FIG. 2, but with several of the partsassembled into a sub-unit;

FIG. 4 is a view similar to FIG. 3, but with even more of the partsassembled together;

FIG. 5 is a view similar to FIG. 4, but with still more of the partsassembled together;

FIG. 6 is another perspective view of the FIG. 1A device, but with thefront cover opened, and refill substrate not yet installed;

FIGS. 7A-7C are enlarged views showing how the device progressivelyappears when starting from the FIG. 6 position, as the refill is movedinto the device;

FIG. 8A shows how the cam will drive the finger clockwise absent arefill being present;

FIG. 8B shows how the presence of a refill can set up the finger to beready for future counterclockwise movement; and

FIG. 8C shows how further movement of the on/off tab once the device hasreached the FIG. 8B position will cause the finger to move furthercounterclockwise to activate the electronics.

DETAILED DESCRIPTION OF THE INVENTION

Referring first to FIGS. 1A, 1B and 2, there is shown a dispensingdevice 10. It has a main housing section 11, an intermediate housingsection 12, an outer cover section 13 and a base cover section 14. Theregion between the main housing section 11 and the base cover section 14houses the primary electrical parts.

In this regard, there are two AA batteries 16 which are in electricalcontact with linkages 17, that in turn are connected to a spring-typeswitch 18, which (when the switch is closed) powers a small motor 19. Anexample of this type of switch is a micro-leaf switch of the sortavailable from the Wealth Metal Factory Ltd. of Hong Kong, China.

The motor 19 has a stem 20. That stem can be linked to the center ofrotor 21 having vanes 24. When the motor receives power, stem 20 rotatesand carries with it the rotor 21. The vanes on the rotor are alignedsuch that the rotation sucks air in through the openings 56 of the outercover section 13 and then forces the air radially outward.

As will be apparent from viewing FIG. 3, there can be formed asubassembly 23 of parts 11, 12, 14 and 16-20. This subassembly iscreated through the use of screws and snap fit connections.

A clip 26 can be mounted to the subassembly 23. Then, table 30 can bemounted so as to position the rotor behind it, yet permitting air topass through its central hole 33.

The table mounts a finger 35 on its outer surface. Initially,spring-type switch 18 is positioned to bias the finger clockwise alongthe finger's longitudinal axis with side extension 38 pointed somewhatoutward. See FIG. 7A for a showing of this “third” position.

Shutter 40 is best understood from FIG. 4. It is bolted to the outercover section 13 with bolt 46 so as to be able to rotate relativethereto. The shutter has triangular closures 41, triangular openings 42,control feet 43 and a control tab 44. It also has a cam projection 48which is generally triangular in side view.

The outer cover section 13 has an oval viewing opening 55 and triangularair openings 56. Note also the cover hinge 51 which permits the cover topivot as shown in FIG. 6, and the locking tab 50 which interacts withelement 52 (shown in FIG. 5) to keep the outer cover section closed whenthat is desired.

Refill unit 60 is generally slab-like. In plan view it has anessentially tear-drop shaped overall appearance, with a generallycircular portion at one end and a generally triangular portion atanother end. There is a spoke support 61 across a circular openingthrough the slab. There is also an arc-shaped slot 63, and a use-up cueshell 66.

Across the spoke support 61 is positioned a fabric 62. When air issucked by the rotor 21, air will be sucked through the fabric 62. Thechoice of the fabric, and its porosity, the speed of the air flow, andthe vapor pressure of the active, are the main factors in coordinatingthe speed of use up of the active with the speed of use up of the use-upcue.

By impregnating the fabric 62 with an appropriate air treatmentchemical, air entering the device will pick up some of the volatilechemical, and dispense it out of the device. Particularly preferredactives are those described in U.S. Pat. No. 6,582,714 or othersynthetic pyrethroids. For use in controlling mosquitoes it is preferredto use metofluthrin from the Sumitomo Chemical Company, Limited (tradename SumiOne). The impregnation material can be pure active, or for easeof handling the material can be dissolved in a hydrocarbon or othersolvent. Alternatively, or in addition, the fabric may also bear afragrance, a deodorizer, or other air treatment chemical.

For mosquito control it is preferred to use an airflow rate through thedevice at about 4 to 6 cubic feet per minute (0.113 to 0.170 cubicmeters per minute). It is also preferred to have the fabric configuredso that the pressure drop across the substrate is no more than 40 Pa.Suitable substrates can be made of woven or non-woven materialsproviding only minimal resistance to the airflow.

The substrate should also be capable of holding active ingredient dosedonto the material and also allow ready migration of the active to thesurface of the substrate so as to allow its evaporation in response tothe airflow. For an active ingredient that is hydrophobic andmigrateable at common environmental temperatures between about 10° C.and 40° C. (e.g. metofluthrin), suitable materials include, only by wayof example, polyester, polypropylene, cotton, cellulose, poly-rayon, andother similar fabrics. These can be non-wovens with basis weightsranging from 10 gsm to 40 gsm, fabricated from synthetic, natural, orcombined synthetic and natural polymeric materials.

The ideal substrate should also allow for wicking of the activeingredient following dosing so as to ensure efficient distributionthroughout the substrate, and thereafter allow migration of activeingredient to the substrate's surface to replenish the active ingredientthat is being evaporated by the passing airflow. Dosing may be bydropping, spraying, printing, or other conventional delivery of a liquidactive ingredient to the substrate. A particularly desirable fabric is anon-woven felted material with a basis weight of 20-30 gsm fabricatedfrom polyethylene terephthalate.

Note that one side of the essentially triangular portion is straight (at65) and the other is indented (at 67). This slight lack of symmetry isdesigned to accommodate a corresponding slight lack of symmetry alongthe top/outer side of table 30, and to thereby prevent a consumer frominstalling the refill unit 60 inside-out.

As shown in FIG. 7A (see also FIG. 8A) when the refill unit is not yetin the device, finger 35 is biased by the spring-type switch 18 (FIG. 2)to a position such that extension 38 is pointed significantlyupwardly/outwardly. When this is the case, attempted movement of theprojection 48 (as the shutter is rotated) would not cause the extension38 to rotate counterclockwise to the FIG. 7B position. Rather it movesonly slightly clockwise until hitting an internal stop. Becausecounterclockwise rotation is needed to cause the spring-type switch 18to complete the circuit to the motor, absent the presence of the refillthe fan won't operate. This sends an immediate message to a consumerthat they need to do something else to make the system work (e.g.install a refill unit).

As the refill is moved into place, as shown in FIG. 7B (see also FIG.8B), it first causes the extension 38 to rotate along the finger'slongitudinal axis from the third to the second position. However, theextent of the rotation at that point is still not enough to cause thefan to turn on. Rather, that occurs only when the projection 48 isprojecting through the arc-shaped slot 63. Then, as the shutter isrotated, the projection 48 is driven along the arc-shaped slot 63 topermit its inward cam end to contact a part of the finger 35. As seen inFIG. 8C, the cam surface of the projection then drives the finger tocomplete its rotation to the “first” position. When this happens thereis sufficient resisting force so as to cause the spring-type switch 18to complete its circuit. Hence, the refill is necessary for any fanoperation, but not sufficient by itself.

Note the multiple functions of the shutter 40. When one moves thecontrol tab 44 from the FIG. 1A position to the FIG. 1B position, thetriangular closures 41 move from a position where they cover openings 56to a position where they let air pass there through as shown in FIG. 1B.At the same time there is a rotation of feet 43 from a position wherethe outlet openings 90 in intermediate housing section 12 are covered toone where they are uncovered. Thus, the shutter can completely close offthe impregnated fabric 62, as well as the use-up cue area, between uses,thereby prolonging their life when the fan is off. The same shuttersystem also controls fan operation.

As described in the co-pending application U.S. Ser. No. 11/609,923,filed Dec. 13, 2006, referred to above, a variety of chemicals can beused to provide a visual indicia of the extent of use by virtue of theirdisappearance or change. As the use-up cue chemical, it is preferred touse a volatile liquid material that diffuses out of a shell, asdescribed in that application. There is dye in the liquid so it can beeasily seen when present. For example, one could use a dye like Fat BlueB 01 available from Clariant.

The shell 64 can be made of transparent polyethylene terephthalate. Forthe use-up cue chemical it is most preferred to place a volatile solventsuch as Norpar 12, a hydrocarbon from ExxonMobil Chemical Company in theuse-up cue shell 64, or to use that with a dye. Then, it is covered witha permeable layer such as an ultra low density polyethylene film (ULDPE)or a low density polyethylene film (LDPE). That is in turn coveredbefore use by an impermeable peel-off layer, such as a peel-off layer orfilm having aluminum foil layer, preferably reinforced by an outerpolyester layer. Immediately prior to use one can then peel off thepeel-off layer, exposing the permeable layer at the back side of theshell.

When the finger 35 is not covering the permeable layer, the volatile canslowly seep out of the shell, providing a visual cue as to the extent ofuse up. This chemical is then blown out of the device by the fan, orotherwise seeps out of the device. As the consumer sees less color inthe transparent window of the shell 64 they will know the use status(because absence of color means the device is used up).

When the device is off, as shown in FIG. 7A, the extension 38 willessentially cover the back side of the use-up cue. Hence, the shutteroperates to avoid premature use up signals.

In operation the device will be clipped on a belt, purse or the likeusing clip 26 for that purpose. Air is sucked by the device in throughopenings 56. As the air passes through fabric 62, the active mixes intothe air and the treated air is then blown radially out outlet openings90 (preferably down along pants or dresses).

While the present device is primarily intended to be used as a wearableitem carried with a human as they watch a game outdoors, or hike, or thelike, it can also be laid flat, with the clip downward and front entryupward, on a picnic table or the like. When used in this manner it canprovide protection to an area during a picnic or similar outdooractivity.

While the preferred embodiment has been described above, it should beappreciated that there are numerous other embodiments of the inventionwithin the spirit and scope of this disclosure. For example, the devicecan be powered by a different source of energy (e.g. a solar powerpanel), other forms of actives can be dispensed along with or insubstitution for the insect control ingredients (e.g. a fragrance ordeodorizing chemical), and even when an insect control ingredient isdispensed it need not be one focused on controlling mosquitoes (e.g.chemicals for repelling other flying or crawling insects or pests can beused). Hence, the invention is not to be limited to just the specificembodiments shown or described.

INDUSTRIAL APPLICABILITY

Provided herein are wearable dispensing devices capable of dispensinginsect control chemicals and/or other air treatment chemicals adjacent ahuman body, and refills for use therewith.

1. A dispensing device for dispensing an air treatment chemical, thedevice comprising: a housing with an inlet and an outlet and anelectrically powered fan to pull air in through the inlet and exhaustthe air through the outlet, creating an air stream through the housing;a switch for turning the fan on and off; a movable shutter that blocksthe air flow when in a first, closed position and allows the air to flowwhen in a second, open position, the shutter having a projection thereonthat interacts with the switch so that moving the shutter to the second,open position activates the switch to turn on the fan; and a rotatablefinger that must be rotated by interaction with the projection of theshutter before the switch is activated, the dispensing device furtherincluding a table to receive and hold a substrate exposed to the airstream, wherein the substrate bears an air treatment chemical to bedispensed, with the substrate held in interactive relation with thefinger so as to partially rotate the finger from a designated positionwhen no substrate is held by the table, to a selected position when asubstrate is held by the table, and wherein when the finger is in theselected position it is further rotated there from by movement of theprojection as the shutter is moved to activate the fan.
 2. Thedispensing device of claim 1, wherein the substrate comprises a use-upcue that changes appearance by evaporation of a material in a directiontoward the table when the substrate is in place on the table, whereinthe finger has a side extension that, as the finger is rotated byinteraction with the projection of the shutter as the shutter is moved,moves from a position inhibiting the evaporation of material from theuse-up cue to a second position wherein evaporation of material from theuse-up cue is readily permitted.
 3. The dispensing device of claim 1wherein the shutter, when in its closed position, closes both the inletand outlet.
 4. A wearable device for dispensing an air treatmentchemical, the device comprising: a housing having an inlet forpermitting air to enter into an internal cavity of the housing and anoutlet for permitting air mixed with air treatment chemical to exit thecavity; a power supply mounted to the housing; a substrate positionablein the housing bearing an air treatment chemical; a blower powered bythe power supply and capable of moving air from the inlet adjacent thesubstrate so as to mix air treatment chemical into the moving air, andthen deliver a mix of air and air treatment chemical to outside of thehousing; and a shutter that controls air flow through the device, andwherein the substrate has an air permeable section bearing the airtreatment chemical and a shell portion containing a volatile use-up cuechemical, the wearable device further comprising: a finger mounted forrotation on its own longitudinal axis; wherein a portion of the fingerpermits diffusion of the use-up cue chemical from the shell when thefinger is in a first rotational position, and restricts diffusion of theuse-up cue chemical from the shell when in a second rotational position,and wherein movement of a cam projection drives the finger from thesecond rotational position to the first rotational position.
 5. Thewearable device of claim 4, wherein the shutter restricts air flowthrough the inlet at a same time the shutter restricts air flow throughthe outlet, when the blower of the device is not operating.
 6. Thewearable device of claim 4, wherein the shutter has linked thereto a camprojection which, when the substrate is in the device and the projectionis moved to a selected position, the projection causes an activation ofthe blower.
 7. The wearable device of claim 6, wherein if the substrateis removed from the device movement of the cam projection to theselected position doesn't activate the blower.
 8. The wearable device ofclaim 4, wherein the finger automatically moves to a third rotationalposition when the substrate is not present, and when so positionedplacing the substrate in the device drives the finger to the secondrotational position.
 9. The wearable device of claim 8, wherein when thefinger is in the second rotational position a cam projection on theshutter extends through a through slot on the substrate to drive thefinger to the first rotational position, and when the finger therebyreaches the first rotational position the blower will be activated. 10.A wearable device for dispensing an air treatment chemical, the devicecomprising: a housing having an inlet for permitting air to enter intoan internal cavity of the housing and an outlet for permitting air mixedwith air treatment chemical to exit the cavity; a power supply mountedto the housing; a substrate positionable in the housing bearing an airtreatment chemical; a blower powered by the power supply and capable ofmoving air from the inlet adjacent the substrate so as to mix airtreatment chemical into the moving air, and then deliver a mix of airand air treatment chemical to outside of the housing; and a shutter thatcontrols air flow through the device, wherein the shutter has linkedthereto a cam projection which, when the substrate is in the device andthe projection is moved to a selected position, the projection causes anactivation of the blower, and wherein if the substrate is removed fromthe device, movement of the cam projection to the selected positiondoesn't activate the blower.
 11. The wearable device of claim 10,wherein the shutter restricts air flow through the inlet at a same timethe shutter restricts air flow through the outlet, when the blower ofthe device is not operating.